As a facsimile system based on the conventional technology, there is a facsimile system which has the multiple message transmission processing function for continuously transmitting a file or files having the same destination for transmission as that of a file currently being transmitted in succession to the file currently being transmitted. In this type of facsimile system a file for each job processing unit called a job file is allocated to one transmission file, and a destination for transmission specified by a user is managed as a destination file corresponding to the transmission file, and access thereto can be made from the job file described above.
Herein description is made for the multiple message transmission processing in the conventional type of facsimile system with reference to FIG. 8 as well as to FIG. 9. It is assumed herein that the facsimile system has two G3 lines, namely G3 line No. 1 and G3 line No. 2, and also that three transmission files, namely transmission files T1 to T3 are accumulated in a specified memory.
Also it is assumed herein that, as shown in FIG. 8, "Destination A; Tokyo Institute" has been specified as a destination for transmission to the transmission file T1, "destination B: Tokyo Institute" and "Destination C: Central Institute" as destinations for transmissions to the transmission file T2, and "Destination D: Central Institute" as a destination for transmission to the transmission file T3.
As shown in FIG. 9, for instance, when the transmission file is being transmitted in the mode of memory transmission through the G3 line No. 1 to "Destination A; Tokyo Institute", as the "destination B: Tokyo Institute" has the same address as "Destination A: Tokyo Institute", the transmission file T2 becomes an object for the multiple message transmission processing, and the transmission T2 is continuously transmitted in succession to the transmission file T1.
At the same time, if the transmission file T3 is being transmitted in the mode of memory transmission through the G3 line No. 2 to the "Destination D: Central Institute", as the "Destination C: Central Institute" has the same address as that of the "Destination D: Central Institute", it is hoped to regard the transmission file T2 as an object for the multiple message transmission processing and to continuously transmit the transmission file T2 in succession to the transmission file T3. However, as the transmission file T2 is now being transmitted in the multiple message transmission mode (or has been specified as an object for the multiple message transmission processing), so that in this case the transmission file T2 can not duplicatedly be treated as an object for the multiple message transmission processing, and the multiple message transmission processing is not executed.
For this reason, the transmission file T2 is transmitted anew when either one of the G3 line No. 1 or G3 line No. 2 becomes available.
As described above, with the conventional technology, when transmission is simultaneously executed through a plurality of communication lines, even in a case where one transmission file (the transmission file T2 in the above case) becomes an object for transmission in each communication line, if the transmission file has been treated as an object for transmission through a different communication line, the transmission file can not be treated as an object for transmission through the communication line, and it is required to wait until any other communication line becomes available and then to call the destination for transmission again for execution of transmission, so that the multiple message transmission processing function can not fully be used, and also there has been problems concerning effective use of communication lines, reduction of communication cost, and efficient utilization of the facsimile system.